Electric zinc-furnace with integral compound resistors and compound condensers.



J. THOMSON. ELECTRIC ZINC FURNACE WITH INTEGRAL COMPOUND RESISTORS AND COMEUUC NU QONDENSERS.

APPLICATION FILED JAN. 2, 1913 1,086,416. Patented Eeb; 1.0, 191

' 2 SHEETS-SHEET 1.

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J. THO msom. ELECTRIC ZINC FURNACE WITH INTEGRAL COMPOUND RESISTORS AND COMPOUND CONDENSERS.

APPLICATION FILED JAN.2,1913.

1,086,416. Patented Feb. 10, 1914.

2 SHEETS SHEET 2.

UNITED STATES PATENT OFFICE.

JOHN THOMSON, OF NEW YORK, N. Y.

CONDENSERS.

To all whom it may concern Be it known that I, JOHN THOMSON, a citizen of the United States, and a resident of the borough of Manhattan of the city of New York, in the county and State of New York, have invented certain new and useful Improvements in Electric Zinc- Furnaces with Integral Compound Resis tors and Compound Condensers, of which the following is a specification, reference being made to the accompanying drawings, forming a part thereof.

This imention relates to the metallurgy of zinc, having for its object the production of zinc-fume by thermo-chemical reaction and the subse uent condensing of said fume to liquid meta A description of the particular means for attainin the desired results and such an elucidatlon of the general principles applicable thereto as seem necessary tor a complete disclosure of the invention are set forth in this specification, reference being had to the accompanying drawings forming a part of said specification and in which drawings a certain specific embodiment is illustrated.

In said drawings Figure l is a transverse center section of a combined furnace and condenser taken on the line A of Fig. 2, the charge and resistor having been removed from the upper or right hand portion of the apparatus. Fig. 2, on the lower or left-hand side of its center line, is a longitudinal cen; ter section, as B or B, of Fig. 1, and on the upper or right-hand side of its center line it is a side elevation to the plane D, D, and a center section from thence through either of the condensers, as C, or C, and Fig. 3 is a diagrammatic section illustrating a detail of the operation.

This 'furnace is particularly intended for the reduction of oxid-of-zinc combined with carbon as therea ent, whereb when ade quately heated su stantially t e following representative reaction ensues, namely:

If pure ZnOand C are used in precisely correct relative pro ortions then the answer of the above formu a is an exact expression of the result in that all of the charged material would be volatilized as zinc-fume and monoxid of carbon; and in which case there would be no residue. Such conditions, how- Specification of: Letters Patent.

Application filed January 2, 1918.

Serial No. 73am.

ever, do not obtain in commercial practice as more or less of inert residual matter will remain depending upon the purity of the materials employed and hence the formula becomes simply representative as above stated. The presence of residual matter in even small quantities is a cause of difliculty in realizing the desired result.

The heat necessary for the decomposition of the charge may be derived either from a superposed rod-resistor or from an underlying bed of carbon resistor or from both.

II is the rod-resistor dis )osed along the longitudinal center of the rnace, its ends being in contact with terminalsd which are suitably connected to the source of power and I is'the bed of carbonresistor which is also interpolated between the terminals 5.

Each of the aforesaid resistors may be sep-' arately electrified or they may be operated in parallel or in series or the bed of carbon resistor may be incited on'a shunt derived from the rod-resistor circuit. The rod-resister is supported upon two series of refractories 6 beneath which are a series of ports 7 for stoking the charge material P contained in side galleries 8.

ported steel channels 10 constitute means whereby continuous openings or slots 12 may be provided through which bars may be introduced for effecting the stoking. This channel construction also rovides for or permits the quick lifting o and ready removal of the side-walls supported thereupon thereby exposing when removed all of the" brick-work which normally underlies the walls on the channels.

The slots 12 may be closed by free bricks,

as 10, when not necessarily open for stoking the char e.

The bed 0 carbon resistor is sustained by a series of spaced grate-bars as 13, which rest on ledges 13, formed in a shallow tamped casing It and beneath the grating is a sump n inwhich inert residualmatter as 14 is collected. In the sides of the casing are a series of lateral openings or ports 15 in the same plane as that of the grate-bars but each of which is in line with the spaces 16 between the saidbars. Part of these orts lead to the right and a part to the eft to the free spaces or chambers e, c of the condensers J, J that are located along side of the tamped casing R. The illars 17 which divide the ports are prefera ly of Patented Feb. 10, 1914.

Suitably supabout the same Width as the ports whereby when the charge-material is stoked in and upon the face of the bed of carbon resistor it will lie in ridges, as see Fig. 3, leaving about equal widths of the bed exposed and in tact sub-dividing the bed of carbon resistor into a series of transverse zones.

The operation may be in several different Ways for example in any of the following several or joint manners: First, the

charge may be decomposed by radiated heat irom the rod-resistor as indicated by the arto supply current to the resistors so that normally the entire mass of the bed of carbon resistor will be heated to a temperature of say 2000 F. and so that the rod-resistor will have a temperature of about 24-00 1 When these conditions are realized the charge is stoked as desired and decomposed by heat derived principally from the rod-resistor. The heat from this rod-resistor flows both to the ridges of charged material and to the exposed portions of the carbon bed. The inert residual matter may sift or percolate by gravity down through the carbon bed and into the sump as indicated by the arrows l9, and the volatilized products of the reaction will also flow directly down and through the said bed to the grating spaces rom whence it flows through the ports as in the manner indicated by arrows 20. In this wise one or" the chief functions of the carbon bed is to eliminate by a secondary reaction should such be required, any pernicious oxidizing agents and thereby deliver clear. fume and gas into the condensing chainhi s. But the carbon bed will also somewhat art from heat imparted thereto by the l'()(.l-l'(.$lf-',t()f to produce a certain proportion of the reaction by dircct'coiuluction of its aci uircd heat to the charge. Another mode of working is to impart the major portion of the elz iergy through the rod-resistor with a cin'tain minor portion from the bed of carbon rosistor. Thus, if the two resistors archmintaincd at about the same temperatute the reacting surfaces of both will be entirely utilized for useful eltect and because of the fact that the condei'iscrs and the charge-material in the ports and galleries largely blanket the sides of the resistors the only loss of energy of any significance will be that omitted to and conducted away from the sump.

hose ire It will be perceived that if the carbon bed requires renewals this can. readily be supplied by stokiug, through the ports.

The fume and gas after reaching the condensing chambers thence flows downwardly through batteries comprising spaced, crossstacked and prc'tcrably staggered plates as 22, 522 ilfliCl also comprising layers of broken carbon as V, to baths of molten zinc 28 and thence through right and left hand por s 24,25, to fines or chambers T, T. These layers of bi ken carbon V may be of such character as" retort-carbon or pieces of broken carbon plates or rods and serve in the nature of a relatively thin filter. This filter is preferably siluatednear to thobottoin of the battery and hence the volume of zinc fume which passes therethrough will be much less than that of the acconnganying monoxid of carbon. Carbon terminals may be employed so that said filter may be operated as an electric resistor whereby the condenser as a whole may be preliminarily heatcd; whereby the liquid zinc in the bottom of the condenser may be preliminarily heated it desired and whereby the temperature within the condenser may be controlled or maintained during a period of intermission.

Another feature of the invention consists in placing two rows of supporting plates, 26, 27, to form three sub fiues or chambers, namely, the right and left fines or chambers T, T and the central flue or chamber Y, all of which are disposed beneath the sump of the resistor casing. The supporting plates do not extend the .full length of the lines but have openings as 28 at each end. Thus the inilowing residual gas enters the central portions of the chamber T and T, deflect right and left, pass th ough the openings 28 again deflect right and left whereby the streams flow toward earh other and finally together pass out through the center tube 29 and thence to the underground or other suitable duct leading to atmosphere.

lildcsircd a small pipe or pipes as 30, may be introduced to the spaces above the baths tor cducting a small quantity or" CO and burning it to (10,, as a test-flame.

Due to the above construction anj, uncondoused iume passing into the central lines or chambers through which the velocity of llow will be quite low, may be collected in the form of metal or as blue-powder, while the heat contained in the gas serves to conserve the heat in the su mp.

A system of circulation may be supplied either for imparting or subtracting heat to or from both Zinc baths by causing a heating medium or cold air as the or so may be, to enter one end of the underlying line L, traversing its length then flowing through a connecting line or pipe as Ill, again along the length of the c iniplonientary flue, L and thence to atmosphere as by the tube 32.

The improvements herein set lfort-h are i not limited to the precise construction and arrangement shown and described and the may be embodied in various forms and modifications without departing from the spirit and scope of the invention.

What I claim is:

1. In an electric furnace a rod resistor and p, which resistors the charge is, located.

'4. An electric furnace whose reaction zone is provided with a rod resistor which acts upon the upper portion of the charge, and a bl'OkItCaIbOI], resistor which acts upon the lower portion of the charge.

5. In an electric zinc Iurnace, a resistor, acting upon the charge by radiated heat, and another resistor acting upon the charge bf,

' conducted heat, the charge being supported resistor and a series of ports in the plane of the space between the two said resistors between the resistors whi of the )roducts of the reaction passing down throng the said carbon bed.

8. In. an electric zinc furnace, a rod-resistor, an underlyin bed of carbon-resistor supported by space gratebars, a sump beneath the gratebars. lateral ports in line with the gratebar spaces and a condenser or condensers connected to the said ports.

9. in an electric zinc furnace, an overlymg rod-resistor, and underlying bed of carthrough which the charge is stoked upon the face of the carbon bed.

'bon and a series of ports in the 10. In an electric zinc furnace an overlying rod-resistor, an underlying bed. of carlane of the s ace between the two throng which the cliarge is stoked upon the face of the carbon bed.

11. In an electric zinc furnace, an overly ing rod-resistor and an underlying bed of carbon resistor, either or both of which may be electrically heated to similar or dissimilar temperatures.

12. In an electric zinc furnace, an inclose d resist-or having adjacentalleries defined by side-walls beneath whic are continuous openings or slots in communication with the bottoms of said galleries.

13. The combination with a source of sup ply of zinc fume, or zinc fume and gas of a condenser or condensers having a battery of cross-stacked members and one or more interposed layers of broken carbon.

14. An electric furnace and condenser having a reaction-chamber sump and a plurality of fines disposed beneath the said sump which are arranged to receive residual gas or gases from the said condenser or condensers.

-15. An apparatus of the class described comprising in combination a rod-resistor, an underlying bed of carbon resist-or, means for inserting charge-material between the said resistors, openings or ports for permitting the escape of the volatilized products of the reaction to a condenser, or condensers, and a sump for collecting the inert residual products of the reaction.

16. In an electric zinc furnace, a bed of carbon adapted to be supplied upon its upper surface with charge-material in separated transverse ridges, and an overlying rod-resistor whose radiant energy acts upon the said ridges and also upon, the exposed intervening s aces of the bed.

. This speci cation signed and witnessed this 31 day of December, A. D. 1912.

JOHNTHOMSON. Signed in the presence ofi EDWIN A. PACKARD, D. HAROLD BUsH. 

